tepochimalli.

Headword: 
tepochimalli.
Principal English Translation: 

metal or iron shield (see Molina and attestations)

Orthographic Variants: 
tepuchimalli
Alonso de Molina: 

tepuchimalli. broquel.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 103v. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

tzinacantopilli, in tepuztlavitolli, in tepuzmitl: yoā no vncan maceoaloc in tepuzquacalalatli, in tepuzvipilli, in tepuzmatlavipilli, in eoachimalli, in tepuchimalli, in quauhchimalli=halberds, crossbows, crossbow, bolts. And also they acquired there iron helmets, iron cuirasses, coats of mail, leather shields, metal shields, wooden shields. (Mexico City, sixteenth century)
James Lockhart, We People Here: Nahuatl Accounts of the Conquest of Mexico, Repertorium Columbianum v. 1 (Los Angeles: UCLA Center for Medieval and Renaissance Studies, 1993), 160.

themes: 
War, Conflict
Weapons, Shields, Heraldry